Two pressure-cooker bombs that tore through the crowd at the 2013 Boston Marathon have forever linked that storied race with the carnage that followed. Three people were killed and 264 more were wounded as runners streamed towards the finish line.
The time line video above recalls the story of how Boston was thrown into chaos and confusion a year ago.
Tune in to The National tonight for Paul Hunter's visit with survivors and victims of the April 15 attack.
Tomorrow, CBC News will live stream coverage of the memorials to commemorate the bombing.
- 12 p.m. ET - U.S. Vice President Joe Biden, Massachusetts Governor L. Deval Patrick, Boston Mayor Martin J. Walsh, emergency responders, and people wounded in last year's bombing attack at the Boston Marathon will attend a memorial ceremony to mark the first anniversary of the deadly blasts.
- 2:35 p.m. ET - A flag will be raised and a moment of silence will take place at the Boston Marathon finish line. Attendees include Biden, Patrick, Walsh, emergency responders, and people wounded in last year's bombing attacks.
- 2:49 p.m. ET - A moment of silence will be observed for the Boston bombing victims.